alt Hacker NewsI’m not sticking up for car manufacturers, but at what size or capacity should you be required to document and publish these things? It requires employer time and effort and has a cost associated with it.
As a counter argument: I was just looking at a small open source utility. As I was going through the code I found cases where certain arguments could be set to magic values that cause useful, but undocumented behavior. Should the developers be forced to document these options?
I don’t think a manufacturer should be able to lock you out of reading diagnostics on your own devices, or that anyone should be prevented from reverse engineering what those values mean. But I also don’t think there should be any requirement that they are forced to do additional work. That seems just as immoral.
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Between reading basic diagnostics and documenting every signal and field is routine or recurring write operations that will need to happen in the field.
Resetting the oil/maintenance light, recoding key fobs, resetting the battery stats upon replacement, etc.
I want independent mechanics to be able to do that. I also want to be able to do that myself, if I’m so inclined.
> I don’t think a manufacturer should be able to lock you out of reading diagnostics on your own devices, or that anyone should be prevented from reverse engineering what those values mean.
But they do do that. Also what’s the difference between a lot of obfuscation and prevention and how will you enforce that without lawsuits and discovery?
Also, what is those values have the ability to do damage and cause safety issues? Like losing your own software onto a control by wire car? Then you can rent a car and install your own software surreptitiously.
the issue is not that this information is undocumented, it's that an "authorized service center" gets information that an "owner" does not. Also cars are not "small open source utilities" with undocumented arguments; do you think that an auto manufacturer has hidden, untested diagnostics that only the dealer uses?
>> don’t think there should be any requirement that they are forced to do additional work
At one time seatbelts, airbags, emission controls, etc were all viewed in this category. Now we have regulations enforcing aspects of all of these. Why would diagnostics be different?
>I’m not sticking up for car manufacturers, but at what size or capacity should you be required to document and publish these things? It requires employer time and effort and has a cost associated with it.
You're talking about things that by definition have to be documented and internally published in order to design and build the powertrain in the first place. You can't design a computer-controlled automatic transmission without documenting the shift points.
The cost is therefore essentially nothing, because the information already exists. Just copy paste it into a PDF and put it on your website.
> It requires employer time and effort and has a cost associated with it.
Intentionally obfuscating the data¹ also requires time effort and costs.
> at what size or capacity should you be required to document and publish these things?
The reason there is an opaque number in that open source utility is precisely because of a lack of open documentation for that register definition. Independent black box analysis of the messages only got as far as "write this value to do effect X". Whomever developed that utility would have loved to spell that bitfield out, but not at the cost of more days reverse engineering.
But manufacturers aren't reverse engineering register definitions, they're working off of vendor datasheets or protocol definitions they themselves created. All of this documentation has already been produced, as it was used to develop the tractor from its various subsystems. It just needs to be published!
> I was just looking at a small open source utility. As I was going through the code I found cases where certain arguments could be set to magic values that cause useful, but undocumented behavior. Should the developers be forced to document these options?
You were able to do that because it was open source. If a car mfr was willing to do that, it would be plenty enough for me. They shouldn't be forced to do any additional work beyond the 5 seconds it takes to type `git remote add origin github.com/honda/civic`. Then the community would have everything it needs to carry things forward.
Failing that, yes, I do think everything should be documented.